ellipsis()
  overflow: hidden
  white-space: nowrap
  text-overflow: ellipsis
border-1px($color)
  position: relative
  &:after
    display: block
    position: absolute
    left: 0
    bottom: 0
    width: 100%
    border-top: 1px solid $color
    content: ' '
border-none()
  &:after
    display: none
bg-image($url)
  background-image: url($url + '@2x.png')
  @media (-webkit-min-device-pixel-ratio: 3), (min-device-pixel-ratio: 3)
    background-image: url($url + '@3x.png')